memory: add a driver for atmel ram controllers

Atmel SoCs have one or multiple RAM controllers that need one or multiple clocks
to run.
This driver handle those clocks.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
This commit is contained in:
Alexandre Belloni 2014-07-08 18:21:12 +02:00 committed by Maxime Ripard
parent 017b5522d5
commit e81b6abebc
3 changed files with 109 additions and 0 deletions

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@ -7,6 +7,16 @@ menuconfig MEMORY
if MEMORY
config ATMEL_SDRAMC
bool "Atmel (Multi-port DDR-)SDRAM Controller"
default y
depends on ARCH_AT91 && OF
help
This driver is for Atmel SDRAM Controller or Atmel Multi-port
DDR-SDRAM Controller available on Atmel AT91SAM9 and SAMA5 SoCs.
Starting with the at91sam9g45, this controller supports SDR, DDR and
LP-DDR memories.
config TI_AEMIF
tristate "Texas Instruments AEMIF driver"
depends on (ARCH_DAVINCI || ARCH_KEYSTONE) && OF

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@ -5,6 +5,7 @@
ifeq ($(CONFIG_DDR),y)
obj-$(CONFIG_OF) += of_memory.o
endif
obj-$(CONFIG_ATMEL_SDRAMC) += atmel-sdramc.o
obj-$(CONFIG_TI_AEMIF) += ti-aemif.o
obj-$(CONFIG_TI_EMIF) += emif.o
obj-$(CONFIG_FSL_IFC) += fsl_ifc.o

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@ -0,0 +1,98 @@
/*
* Atmel (Multi-port DDR-)SDRAM Controller driver
*
* Copyright (C) 2014 Atmel
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
struct at91_ramc_caps {
bool has_ddrck;
bool has_mpddr_clk;
};
static const struct at91_ramc_caps at91rm9200_caps = { };
static const struct at91_ramc_caps at91sam9g45_caps = {
.has_ddrck = 1,
.has_mpddr_clk = 0,
};
static const struct at91_ramc_caps sama5d3_caps = {
.has_ddrck = 1,
.has_mpddr_clk = 1,
};
static const struct of_device_id atmel_ramc_of_match[] = {
{ .compatible = "atmel,at91rm9200-sdramc", .data = &at91rm9200_caps, },
{ .compatible = "atmel,at91sam9260-sdramc", .data = &at91rm9200_caps, },
{ .compatible = "atmel,at91sam9g45-ddramc", .data = &at91sam9g45_caps, },
{ .compatible = "atmel,sama5d3-ddramc", .data = &sama5d3_caps, },
{},
};
MODULE_DEVICE_TABLE(of, atmel_ramc_of_match);
static int atmel_ramc_probe(struct platform_device *pdev)
{
const struct of_device_id *match;
const struct at91_ramc_caps *caps;
struct clk *clk;
match = of_match_device(atmel_ramc_of_match, &pdev->dev);
caps = match->data;
if (caps->has_ddrck) {
clk = devm_clk_get(&pdev->dev, "ddrck");
if (IS_ERR(clk))
return PTR_ERR(clk);
clk_prepare_enable(clk);
}
if (caps->has_mpddr_clk) {
clk = devm_clk_get(&pdev->dev, "mpddr");
if (IS_ERR(clk)) {
pr_err("AT91 RAMC: couldn't get mpddr clock\n");
return PTR_ERR(clk);
}
clk_prepare_enable(clk);
}
return 0;
}
static struct platform_driver atmel_ramc_driver = {
.probe = atmel_ramc_probe,
.driver = {
.name = "atmel-ramc",
.owner = THIS_MODULE,
.of_match_table = atmel_ramc_of_match,
},
};
static int __init atmel_ramc_init(void)
{
return platform_driver_register(&atmel_ramc_driver);
}
module_init(atmel_ramc_init);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@free-electrons.com>");
MODULE_DESCRIPTION("Atmel (Multi-port DDR-)SDRAM Controller");